What is a Brim in 3D Printing and Why It Matters

A 3D print brim helps stabilize prints by increasing surface area around the base layer. Learn how and when to use a brim in 3D printing for better results.

Upside Parts - Brim in 3D Printing

Brims are a small but powerful feature in FDM 3D printing. They increase surface area, reduce edge lift, and improve print success rates on challenging parts or materials. In our daily production, a brim is sometimes the difference between a high-quality result and a failed print.

What is a 3D Print Brim and Why Does It Matter

A brim in 3D printing is a set of extra lines printed flat on the build plate around the base of your model. These lines touch the part but do not extend underneath it. The brim is meant to improve adhesion to the bed and reduce the risk of warping or shifting during printing.

Brims are different from skirts and rafts. A skirt surrounds the model but does not touch it, mainly used to prime the nozzle. A raft creates a complete platform under the part. Brims offer a middle-ground solution that helps parts stick without adding excessive material or post-processing time.

Most modern slicers, including Cura and Bambu Studio, can automatically generate brims when needed. The brim appears as a thin ring around the model base and is usually just a few millimeters wide.

In our work, we find brims to be a low-effort way to solve many adhesion issues, especially for narrow or tall parts. They provide extra grip and hold down edges that may lift during printing.

Benefits of Using a Brim in 3D Printing

The main benefit of a brim in 3D printing is improved bed adhesion. Brims hold down the edges of a print during the early layers, helping prevent the corners from curling or detaching. This becomes especially important when using materials known for shrinkage, such as ABS, ASA, nylon, or polycarbonate.

Brims also increase the stability of tall or angled models. When a part has a small footprint or is oriented at 45 degrees, the brim adds grip where the part touches the bed. This support helps prevent prints from tipping or failing early in the process.

In our practical experience, brim use also helps during prints with high infill settings. When the model has more than 50 percent infill, the internal forces during cooling can cause the edges to pull up. A well-placed brim resists these forces by anchoring the base more securely to the bed.

At our company, we use brims often when printing with difficult materials or when running parts that need extra stability. It’s a simple tool that prevents larger issues.

When to Use a 3D Printer Brim and When to Avoid It

Brims are most helpful in the following situations:

• The part is tall and narrow, with minimal surface contact on the bed

• The model is printed at an angle, such as 45 degrees, increasing the chance of lift

• You are working with materials that shrink or warp, including ABS, nylon, ASA, or PC

• The infill percentage is high, typically above 50 percent

• The part has sharp corners or thin features at the base that are likely to peel

In these cases, the brim acts like a tension ring. It reduces the chance of print failure by spreading thermal forces across a wider area.

However, there are times when using a brim adds unnecessary work or causes problems:

• The part already has a large base and adheres well without support

• The model is made from a low-shrink material like PLA

• The geometry is complex and difficult to clean after printing

• The print will require extra finishing, and removing the brim would be time-consuming

In our production work, we choose not to use brims on parts with organic shapes or complex cutouts where the brim would be hard to remove. Time spent cleaning up a brim can outweigh its benefits if the base is already stable.

You may also be interested in reading our post on how to make 3D models for printing and save money. 

Practical Insights from Production Use

As a professional 3D printing service, we rely on brims for both consistency and success on tough jobs. Our engineers typically add a brim when the part is tall, printed at an angle, or made from a material known for warping. 

We also monitor how much post-processing a 3D printer brim will require. If the part is detailed near the bottom or needs clean edges, we weigh the benefit of added adhesion against the cleanup time. This is especially relevant for complex geometries or parts that will be dyed or painted.

Materials that give us the most trouble with edge lift include ABS, ASA, nylon, and polycarbonate. For these, a brim is often the default setting in our slicer profiles.

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